Unique ageing study shapes understanding of human health

It is an extraordinary piece of medical research that has been going on for nearly seven decades.

Scientists have been monitoring the health of a group of people who were all born in the same week in March 1946.

Their findings have already helped to shape NHS treatments.

Now, as those people approach their 70s, it is hoped the latest phase of the study can advance the understanding of Alzheimer's.

The BBC's Tim Muffett reports.